Add GTM key to a new .env.development.local file in /client

// client/.env.development.local
REACT_APP_GTM_ID=<GTM Container ID>

Current GTM Staging Container ID: GTM-TT348T3

// restart docker containers to load in new env key
docker-compose down
docker-compose up

Request access to Google Tag Manager account in #business-intelligence

Disable ad blockers on tagmanager.google.com and also your localhost:3000 before continuing.